Available at: http://digitalcommons.calpoly.edu/theses/1096
Date of Award
MS in Engineering - Materials Engineering
Dr. Linda Vanasupa
Biochar’s high porosity and negative surface charge allows for numerous soil and plant benefits such as increased water retention, high nutrient availability, and plant growth. By analysing biochar’s effect of all of these factors, a system can be put in place in which soils can be remediated with the proper soil amendments. This report discusses and tests the effects of varying rates of biochar on pH levels, cation exchange capacity, and nutrient exchangeability (of calcium, magnesium, sodium, and potassium) in soil. Corn plants were also grown in soils of varying amendment types and analysed for plant growth and germination to determine soil effects on the plant.
Testing showed significant differences between treatment types in all areas tested except plant germination. A 2:1 ratio of biochar to compost produced the best overall results for the soil used in testing. This treatment maintained acceptable levels of exchangeable nutrients while raising pH and cation exchange capacity, and also raised the plant growth in the soil by 30%. However, for added soil health, gypsum or calcium fertilizer should be added to the soil to remediate low calcium exchangeability. This testing confirmed that biochar does have a strong positive influence on soil and plant health when used in combination with compost.